A well designed vortex flowmeter comprising a planar vortex sensor disposed downstream of the vortex generating bluff body of an elongated cylindrical shape measures velocity of fluid flow in a range wherein the ratio of the maximum measurable velocity to the minimum measurable velocity approaches or exceeds one hundred to one, when the mechanical vibrations of the flow conduit and flowmeter body is kept at the minimum level, which performance of the vortex flowmeter has been demonstrated by a number of different vortex flowmeters invented and designed by this inventor, which vortex flowmeters measure the velocity of air flow under the standard condition ranging from one meter per second to one hundred and fifty meters per second, and water flow ranging from 0.1 meter per second to fifteen meters per second. In order to duplicate this amazing performance of the vortex flowmeter demonstrated under laboratory conditions in actual field conditions, the vortex flowmeter must have an active noise cancelling means in processing the electrical signal representing the vortices as well as the mechanical vibrations of flowmeter body, which electrical signal is provided by the transducer included in the planar vortex sensor.